sm(_at_)resistor(_dot_)net writes:
Hi Arnt,
At 10:01 15-04-2008, Arnt Gulbrandsen wrote:
However, I think 2821bis needs a little extra text to notify
operators that they may need to upgrade or reconfigure to comply
with 2821bis. For example bs.jck.com currently refuses mail from
AAAA-only addresses:
There's nothing wrong with that if the host is only IPv4 aware. The
IPv6-only sender would be connecting to the IPv6 relay for that
domain to send mail as follows:
MAIL FROM:<test(_at_)ipv6(_dot_)l(_dot_)google(_dot_)com>
250 OK
RCPT TO:<jklensin(_at_)jck(_dot_)com>
250 Accepted
Yes, and the IPv6-only relay would then connect to bs.jck.com and
issuing the conversation that ends with 550.
Exim users can comply by disabling the sender_verify variable,
postfix users can disable reject_unknown_sender_domain, I don't know
the relevant variable for any other MTAs.
That might cause more problem than it solves.
I agree.
Arnt